The 'Hunger Games' star gets candid about weight, boyfriend, living with her parents, more.

"I never know what's going to come out of my mouth, and it's horrible," she says in the December issue of Elle. "I don't find it positive in any way. When I get older, I'll be more mature and poised. And I'll have control over my mouth. One day, I'm going to grow up…"

But her remarks about her weight are spreading quickly and earning her kudos. "In Hollywood, I'm obese," she says. "I'm considered a fat actress."

But she says she's not going to cave in. The Hunger Games star, who played heroic main character Katniss Everdeen, knows she's a role model to many young fans.

"I'm never going to starve myself for a part… I don't want little girls to be like, 'Oh, I want to look like Katniss, so I'm going to skip dinner. That's something I was really conscious of during training, when you're trying to get your body to look exactly right. I was trying to get my body to look fit and strong — not thin and underfed."

Lawrence also opened up about her relationship with British actor Nicholas Hoult: "[My boyfriend] is honestly my best friend, and hopefully I'm his best friend too. He's my favorite person to be around and makes me laugh harder than anybody."

And about her living arrangements, she says, "Ten million dollars and I'm still living in my parents' condo. ... I've always lived in a tiny rat-infested apartment in New York, or a little condo in L.A., or a normal house in Kentucky. I think it would be very bizarre to live in a big mansion by myself."